Bainbridges, the auction house, said that the final price for the 30cm-inch vase - an imperially commissioned piece decorated with a fish motif - far exceeded the pre-auction estimated price, which was about £1.2 million.
The final amount was thought to be among the highest ever paid for any Chinese artwork sold at auction.
After fierce competition among Chinese buyers, the vase was bought by a Chinese bidder who turned up to bid on behalf of an undisclosed buyer.
The auction house - a small, independent company in the London suburb of Ruislip that runs auctions and valuations for people clearing their homes - said the vase is of exceptional quality and that it knew the estimated price was "a bit conservative."
Still, the final price was beyond all expectations.
"The rumours grew as more people came to see it ... but we had no idea it would go for this price," Helen Porter, a spokeswoman at Bainbridges.
The vase was found in "an ordinary home," Porter said. It is believed to have been acquired by an English family during the 1930s or earlier.
